Benchmark Barrels uses only the highest quality 416R and 4140R carbon steel in the production of their product. This ensures that their barrel is the finest you can put on your rifle.All barrels are individually double hand lapped to a true consistent bore. The manufacturing process also includes double stress relieving and quality control inspection utilizing proprietary methods along with the most accurate industry techniques available.The chambering and threading process consists of the most modern CNC and fixturing techniques in the firearms industry. These methods produce the straightest and most uniform threads and chambers.These barrel blanks use a 5R rifling